54 results about "O-nitrotoluene" patented technology

The invention relates to a process for preparing aromatic aldehydes, in particular a process for preparing p-nitrobenzaldehyde through bionic catalytic oxidation of p-nitrotoluene, wherein metallic phthalocyanine, single nuclear metalloporphyrin or mu-oxy-double nuclear metalloporphyrin having the similar structure as the biological enzymes are selected as the catalyst for the disclosed process, whose dose is 0.1-1.0% weight of p-nitrotoluene, and methyl alcohol is used as solvent, 0.5-3.0 MPa oxygen is let into 0.7-2.8 mol / L strong alkaline methyl alcohol solution, controlling the reaction temperature to be 20-65 deg. C, the reaction time being 6-48 hrs.

The invention discloses a method for synthesizing a pyraclostrobin intermediate. The synthetic method comprises the following steps: preparing an intermediate 1-(4-chlorophenyl)-3-hydroxy-1-h-pyrazole from 4-chlorophenylhydrazine hydrochloride prepared with p-bromochlorobenzene and hydrazine hydrate as reaction raw materials; reacting o-nitrotoluene with chlorine in the presence of a catalyst so as to prepare o-nitrobenzyl chloride; and subjecting 1-(4-chlorophenyl)-3-hydroxy-1-h-pyrazole and o-nitrobenzyl chloride to an etherification reaction so as to obtain the pyraclostrobin intermediate, i.e., an etherification product 2[(N-4-chlorophenyl)-3-pyrazolyl-oxymethyl]nitrobenzene. The synthetic method provided by the invention can greatly reduce the amount of waste water produced in the synthesis process of 4-chlorophenylhydrazine hydrochloride; with 4-chlorophenylhydrazine hydrochloride as a raw material, the produced intermediate 1-(4-chlorophenyl)-3-hydroxy-1-h-pyrazole has HPLC content of no less than 98% and yield of no less than 90%; since chlorine is used for replacing bromine or hydrobromic acid to prepare o-nitrobenzyl bromide, production cost and environmental protection burden are controlled; and the etherification product with a content of no less than 98% and yield of no less than 90% is obtained.

The invention relates to a novel nitrobenzyl bromide synthesis process which comprises the following steps: in the presence of 40% hydrobromic acid, 30% hydrogen peroxide and an initiator, namely azodiisobutyronitrile, by taking ortho-nitrotoluene as a raw material, performing a free radical bromination reaction, thereby synthesizing the nitrobenzyl bromide. The 30% hydrogen peroxide is adopted asan oxidant in the process, bromine is provided by oxidizing the hydrobromic acid, the testing conditions are strictly regulated and controlled, then the free radical bromination reaction of the ortho-nitrotoluene has selectivity, the synthesis procedures are controllable, no dibromo-byproduct is generated, meanwhile the yield is far greater than that of the prior art, the production cost is low,the environment is protected, and the process is an ideal method applicable to large-scale industrial production at present.

The invention discloses a method for preparing 2-amino-4'-fluorobenzophenone. The method comprises the following steps: o-nitrotoluene, trichloroisocyanuric acid, tetramethylpiperidine nitrogen oxideand sodium bromide undergo an oxidation reaction to obtain o-nitrobenzoic acid; the o-nitrobenzoic acid and trichloromethyl carbonate undergo an acylating chlorination to obtain o-nitrobenzoyl chloride; the o-nitrobenzoyl chloride, fluorobenzene and aluminum trichloride undergo a Friedel-Crafts reaction to obtain 2-nitro-4'-fluorobenzophenone; and the 2-nitro-4'-fluorobenzophenone is reduced by hydrogen to the 2-amino-4'-fluorobenzophenone. The method has the advantages of green and environmentally-friendly synthesis route, cheap and easily available initial raw materials, low cost, convenience in operation, suitableness for industrial production, and high yield, and the prepared 2-amino-4'-fluorobenzophenone has a good purity.

The invention relates to a method for efficiently and rapidly synthesizing anthranilaldehyde from o-nitrotoluene in one step using an environmentally friendly catalyst under mild reaction conditions. In the presence of sodium polysulfide, anthranilaldehyde can be synthesized from o-nitrotoluene in one step using alcohol as a solvent. The catalytic effect of ionic liquid is remarkable.

The invention discloses a synthesis process of pyraclostrobin intermediate o-nitrobenzyl bromide, which comprises the following steps: adding chlorobenzene, hydrobromic acid solution and a catalyst into a reaction kettle, raising the temperature; Add o-nitrotoluene and hydrogen peroxide solution, and continue to keep warm for 2 hours; put concentrated sulfuric acid and zinc powder into the reaction kettle in turn, control the temperature between 85-90°C, keep warm for 1 hour; let stand to separate layers, and separate the lower layer The organic phase was sampled and analyzed to obtain o-nitrobenzyl bromide. The content of o-nitrobenzyl bromide obtained by the synthesis process of o-nitrobenzyl bromide of the present invention is more than 75%, and the content of by-product dibromine is below 0.5%. Compared with the old technology, it has high yield and few by-products characteristics, and the synthesis process does not require additional equipment, the process operation is simple, and the economic benefit is high.